A retired L&H employee told me that the Washburn harps were made before WWI so that a less expensive instrument could be sold through independent music stores. The regular L&H brand harps were sold only through L&H stores, of which there were several in major cities. The ones we have worked on were identical to the early Style 20 harps except that they had plain veneer instead of the figured maple veneers used on the more expensive harps.
From your description it sounds as if it needs regulation and some cosmetic work, which is not very expensive. The ones we have seen were not bronze unless someone has sprayed them with “radiator paint”, but were actually gilded with 22 kt gold leaf.